Plane powered by 50kg electric motor 'will change aviation'

04 July, 2016

An aircraft powered by a 50kg electric motor with a continuous output of 260kW has flown for the first time, from an airfield in northern Germany. The two-seater plane – an adapted aerobatic craft built by Extra Aircraft – flew for ten minutes on its maiden flight in June. Its developers believe that it could be the forerunner for hybrid-electric aircraft with four or more seats that will cut fuel consumption and emissions by up to 50%, as well as reducing noise levels dramatically.

The 580V motor, specially developed by Siemens, has a power-to-weight ratio of 5kW/kg – said to be five times higher than conventional motors. It has a top speed of 2,500 rpm, an efficiency of 95%, and a torque rating of 1kNm.

“This day will change aviation,” predicts Frank Anton, head of eAircraft at Siemens' corporate technology research unit. “This is the first time that an electric aircraft in the quarter-megawatt performance class has flown.”

The Extra 330LE aircraft, which weighs less than 1,000kg, will serve as a flying test bed for the new propulsion system. As an aerobatic plane, it is ideal for taking components to their limits.

The 8m-wingspan aircraft has been developed by Siemens in collaboration with Extra, the Bavarian propeller-maker MT-Propeller and a Slovenian company called Pipistrel which supplied the batteries. The German government has supported the project via its Aeronautics Research Programme (LuFo).

Siemens wants to establish hybrid-electric propulsion systems for aircraft as a future area of business. It will be contributing its motor technology to the collaborative project that it set up with Airbus earlier this year to develop electrically powered flight. The partners plan to use the scalable motor as a basis for regional airliners powered by hybrid-electric propulsion systems.

The two-seater electric aircraft, based on an aerobatic plane, takes off in Germany

“By 2030, we expect to see initial aircraft with up to 100 passengers and a range of around 1,000km,” says Anton.

“The first flight of our propulsion system is a milestone on the road to electrification of aviation,” adds Siemens’ chief technology officer, Siegfried Russwurm.

“To continue this journey successfully,” he continues, “we need disruptive ideas and the courage to take risks. That's why the development of electric propulsion systems for aircraft is also the first project for our new start-up organisation, next47.”

Siemens plans to invest €1bn in start-up businesses over the coming five years via next47, which will have offices in China and the US, as well as Germany. Planned areas for investment include artificial intelligence, autonomous machines, decentralised electrification and networked mobility.

The aircraft's motor, inverter and batteries are installed in a tubular lattice frame